Answer:
4x^2 +9xy +6y^2
Step-by-step explanation:
Combine like terms. I find it useful to factor out the variable part of the expression so I can see what coefficients are being combined.
7x^2+5xy-3y^2 - (2x^2+3xy-5y^2 + x^2-7xy-4y^2)
= (7 -2 -1)x^2 +(5 -3+7)xy +(-3 +5 +4)y^2
= 4x^2 +9xy +6y^2
Answer:
Sam made a mistake, and their correct value is 30.
Step-by-step explanation:
slope is change in y over change in x
use 2 points from the table so -3,-21 and -6,-39
change in Y: -39 - -21 = -18
change in x = -6 - -3 = -3
slope = -18/-3 = 6
slope = 6
Answer:
140°
Step-by-step explanation:
total angle of a hexagon is 720. We know already 510°. That leaves 210°. The ratio between the two angles is 2:1, therefore angle CDE is 140° and angle DEF is 70 °